heavily in your favor that it is merely a stray intruder.
Third, consider the symptoms. Has your friend experienced persistent itching? While some people react immediately, the intense itching associated with head lice is an allergic reaction to the insect’s saliva. This reaction typically takes several days or even weeks of consistent feeding to develop. A sudden, isolated itch is more likely due to a dry scalp or a stray hair.
What Head Lice Actually Look Like
To help you confidently rule them out, it is useful to know the